1. Field
The disclosure relates to a method, system, and article of manufacture for the adjustment of a tape writing mechanism, based on tape dimensional stability and positional error signal distribution.
2. Background
In the design of a tape drive system, the expansion and contraction of the magnetic tape may have to be taken into account. Such expansions and contractions of the magnetic tape cause a Change in the dimension of the magnetic tape. Such dimensional changes of the magnetic tape may be caused by environmental factors, via aging of the magnetic tape, and via other factors. For example, a magnetic tape may change its dimensions when exposed to different temperatures and humidities. Such changes in the dimension of the magnetic tape may impact the successful reading of data that has been previously written on the tape under a different environment condition.
Tape Dimensional Stability (TDS) is a measure of the positional stability of the magnetic data tracks relative to each other and is a function of the tape properties and environmental effects such as temperature, humidity, tension, creep, etc. These environmental factors can cause the tape to expand or contract laterally, across the width of the tape. Therefore, when a tape is written to in one environmental condition and subsequently read from in another environmental condition, the position of the data tracks across the tape width can change enough to cause signal degradation or read errors. Minimizing tape dimensional changes may ensure the robustness of the reading data in a different environmental condition.
In a tape drive, a head assembly of a tape drive may include servo heads that read data from servo tracks or bands on the tape. Mechanisms may be included in the tape drive to analyze data from the servo tracks to generate a position error signal (PES), and the PES may used by the tape drive to position the head assembly on the tape. A larger standard deviation in the PES means that the edges of the magnetic recording of data on the tape are more jagged in comparison to a smaller standard deviation in the PES.